Hybrid modular storage fetching system

ABSTRACT

A hybrid modular storage fetching system is described. In an example implementation, the system may include a warehouse execution system adapted to generate a picking schedule for picking pick-to-cart and high-density storage items, and an AGV dispatching system adapted to dispatch a cart automated guided vehicle and a modular storage fetching automated guided vehicle based on the picking schedule. The cart automated guided vehicle may be adapted autonomously transport a carton through a pick-to-cart area and to a pick-cell station. The modular storage fetching automated guided vehicle may be adapted to synchronously autonomously transport a modular storage unit containing items to be placed in the cartons from a high-density storage area to the pick-cell station.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. § 119(e) of U.S.Provisional Application No. 62/403,001, entitled “Modular StorageFetching System (MSFS),” filed on Sep. 30, 2016, the entire contents ofwhich are incorporated herein by reference.

BACKGROUND

This application relates to inventory management systems (e.g., orderdistribution or fulfillment systems).

Some current inventory management systems use drag-along carts on whichhuman agents (pickers) place items they select (pick) to fulfill orders.In a zone-less pick-to-cart system an agent drags his/her cart fromlocation to location as instructed by the computer system of thefacility. The cart can accommodate multiple orders and typically isequipped with dedicated containers or cartons that are keyed to theorders being fulfilled by the agent during that cart load. In somecases, the agent wears a headset and/or is provided a terminal, such asa mobile computing device, via which the agent is provided ordered,item-by-item instructions on which items to pick. As the agent walksaround the facility among the different fixed shelving units, he/shedrags or pushes his/her cart manually. During a given shift, the agentmay end up considerably fatigued from having to propel the cart aroundthe warehouse.

Further, some current inventory management systems divide inventory intoa series of zones and assign a human agent to a zone. The systems mayuse a conveyor belt to move orders across the zones as controlled by thecomputer system of the facility. In some cases, the agent wears aheadset and/or is provided a terminal, such as a mobile computingdevice, via which the agent is provided ordered, item-by-iteminstructions on which items to pick. In some cases, pick-to-lightsystems use light displays to direct operators to product locations.Each product location has a numeric or alphanumeric display with alight, an acknowledgement button, and a digital readout for indicatingquantity.

Further, some current inventory management or distribution systems use a“goods-to-person” approach where the items to be picked by a human agentare brought to a predetermined location to eliminate the amount ofwalking the human agent must do within a facility and/or expedite thepicking of the items by the picker. Once picked, these items arepackaged and dispatched. While these systems may, in certain use cases,adequately maneuver the items to the stations at which they are to bepicked, they are less effective for high-volume and/or high-velocitygoods because they have to continually return the same goods to thepicking stations during the course of a day.

SUMMARY

A system can be configured to perform particular operations or actionsby virtue of having software, firmware, hardware, or a combination ofthem installed on the system that in operation causes or cause thesystem to perform the actions. One general aspect includes a methodincluding: generating, by one or more computing devices, a pickingschedule including pick-to-cart routing based on order data, the orderdata including one or more first identification codes representing oneor more first items located in a pick-to-cart area of a distributionfacility; transmitting, by the one or more computing devices, a signalincluding the picking schedule to an automated guided vehicle (AGV)dispatching system; dispatching, by the AGV dispatching system, a cartAGV according to the picking schedule, the cart AGV including a driveunit adapted to provide motive force to the cart AGV and a guidancesystem adapted to locate the cart AGV in the distribution facility, thecart AGV adapted to autonomously transport cartons, the cartons adaptedto hold items; autonomously navigating, by the one or more computingdevices, the cart AGV through the pick-to-cart area according to thepick-to-cart routing to allow picking of the one or more first itemslocated in the pick-to-cart area; and autonomously navigating, by theone or more computing devices, the cart AGV to a pick-cell stationaccording to the pick-to-cart routing. Other embodiments of this aspectinclude corresponding computer systems, apparatus, and computer programsrecorded on one or more computer storage devices, each configured toperform the actions of the methods.

Implementations may include one or more of the following features. Themethod may also include that the order data includes one or more secondidentification codes representing one or more second items located in ahigh-density storage area of the distribution facility. The method mayalso include that the picking schedule includes modular storage fetching(MSF) routing. The method may also include dispatching, by the AGVdispatching system, an MSF AGV according to the picking schedule, theMSF AGV including a drive unit adapted to provide motive force to theMSF AGV, a guidance system adapted to locate the MSF AGV in thedistribution facility, and a modular storage unit holder adapted to holdmodular storage units, the MSF AGV adapted autonomously retrieve one ormore modular storage units from the high-density storage area andtransport the one or more modular storage units to the pick-cellstation, autonomously navigating, by the one or more computing devices,the MSF AGV to a location of the one or more modular storage units inthe high-density storage area, the one or more modular storage unitscontaining the one or more second items, and autonomously retrieving, bythe MSF AGV, the one or more modular storage units from the high-densitystorage area. The method may further include autonomously navigating, bythe one or more computing devices, the MSF AGV from the location of theone or more modular storage units in the high-density storage area tothe pick-cell station according to the MSF routing. The method may alsoinclude autonomously navigating the MSF AGV to the location of the oneor more modular storage units in the high-density storage area includesautonomously navigating the MSF AGV to a first location of a firstmodular storage unit in the high-density storage area, the first modularstorage unit containing a first particular item of the one or moresecond items, and autonomously navigating the MSF AGV from the firstlocation of the first modular storage unit to a second location of asecond modular storage unit, the second modular storage unit containinga second particular item of the one or more second items. The method mayalso include autonomously retrieving, by the MSF AGV, the one or moremodular storage units, autonomously retrieving, by the MSF AGV, thefirst modular storage unit from the first location of the first modularstorage unit in the high-density storage area, and autonomouslyretrieving, by the MSF AGV, the second modular storage unit from thesecond location of the second modular storage unit. The method where thesecond location of the second modular storage unit is a second pick-cellstation. The method where the second location of the second modularstorage unit is a different location of the high-density storage areathan the first location of the first modular storage unit. The methodmay also include autonomously navigating the MSF AGV from the locationof the one or more modular storage units in the high-density storagearea to the pick-cell station. The method may also include autonomouslydelivering, by the MSF AGV, the first modular storage unit to thepick-cell station. The method where the MSF AGV is further adapted tostage the one or more modular storage units at a staging area of thepick-cell station. The method where the MSF AGV is adapted to retrievemultiple sizes of modular storage units. The method may also includethat the one or more modular storage include and a holding structureadapted to hold items, the holding structure adapted to interface with aretrieval mechanism of the MSF AGV. The method may also include that theMSF AGV includes the retrieval mechanism adapted to interface with theholding structure to retrieve a given modular storage unit from amodular storage unit support structure and place the given modularstorage unit in the modular storage unit holder. The method may alsoinclude that the retrieval mechanism of the MSF AGV includes a forkcoupled with the MSF AGV and is configured to lift the given modularstorage unit and remove the given modular storage unit from the modularstorage unit support structure. The method may also include that themodular storage unit support structure includes a shelf. The method mayalso include that the modular storage unit holder of the MSF AGV isadapted to hold a plurality of modular storage units. The method mayalso include that the modular storage unit holder of the MSF AGVincludes a plurality of bays, each bay adapted to hold a modular storageunit. The method may also include that the retrieval mechanism isadapted to place the given modular storage unit in any of the pluralityof bays. The method where the pick-cell station includes an outputdevice configured to provide picking instructions to a picker, thepicking instructions indicating to the picker which of the one or moresecond items from the one or more modular storage units to place in agiven carton held on the cart AGV. The system further including an MSFAGV including a drive unit adapted to provide motive force to the MSFAGV, a guidance system adapted to locate the MSF AGV in the distributionfacility, and a modular storage unit holder adapted to hold modularstorage units, the MSF AGV adapted autonomously retrieve one or moremodular storage units from the high-density storage area and transportthe one or more modular storage units to the pick-cell station. Thesystem where the MSF AGV is further configured to autonomously navigateto a location of the one or more modular storage units in thehigh-density storage area, the one or more modular storage unitscontaining a second item, and autonomously retrieve the one or moremodular storage units from the high-density storage area. The systemwhere the MSF AGV is further configured to autonomously navigate fromthe location of the one or more modular storage units in thehigh-density storage area to the pick-cell station, and autonomouslydeliver the one or more modular storage units to the pick-cell station.The system where the AGV dispatching system is further configured todispatch a MSF AGV according to the picking schedule. Implementations ofthe described techniques may include hardware, a method or process, orcomputer software on a computer-accessible medium.

Another general aspect includes a method including: dispatching, by anAGV dispatching system, a cart AGV according to a picking schedule, thecart AGV including a drive unit adapted to provide motive force to thecart AGV and a guidance system adapted to locate the cart AGV in adistribution facility, the cart AGV adapted to autonomously transportcartons, the cartons adapted to hold items; dispatching, by the AGVdispatching system, a MSF AGV according to the picking schedule, the MSFAGV including a drive unit adapted to provide motive force to the MSFAGV and a guidance system adapted to locate the MSF AGV in thedistribution facility, the MSF AGV adapted to hold a plurality ofmodular storage units and retrieve the plurality of modular storageunits from a high-density storage area and transport the plurality ofmodular storage units to a pick-cell station; autonomously navigating,by the one or more computing devices, the cart AGV through apick-to-cart area according to the picking schedule to retrieve a firstitem located in the pick-to-cart area; autonomously navigating, by theone or more computing devices, the cart AGV to the pick-cell stationaccording to the picking schedule; autonomously navigating the MSF AGVto a first location of a first modular storage unit in the high-densitystorage area, the first modular storage unit containing a second item;autonomously retrieving, by the MSF AGV, the first modular storage unitfrom the first location; autonomously navigating the MSF AGV from thefirst location to a second location of a second modular storage unit,the second modular storage unit containing a third item; autonomouslyretrieving, by the MSF AGV, the second modular storage unit from thesecond location; and autonomously delivering, by the MSF AGV, the firstmodular storage unit and the second modular storage unit to thepick-cell station. Other embodiments of this aspect includecorresponding computer systems, apparatus, and computer programsrecorded on one or more computer storage devices, each configured toperform the actions of the methods.

Another general aspect includes a system including: a warehouseexecution system adapted to generate a picking schedule includingpick-to-cart routing based on order data, the order data including oneor more first identification codes representing one or more first itemslocated in a pick-to-cart area of a distribution facility, and transmita signal including the picking schedule to an AGV dispatching system; anAGV dispatching system adapted to dispatch a cart AGV according to thepicking schedule, the cart AGV including a drive unit adapted to providemotive force to the cart AGV and a guidance system adapted to locate thecart AGV in the distribution facility, the cart AGV adapted toautonomously transport cartons, the cartons adapted to hold items; andthe cart AGV adapted to autonomously navigate through the pick-to-cartarea according to the pick-to-cart routing to retrieve the one or morefirst items located in the pick-to-cart area, autonomously navigate to apick-cell station according to the pick-to-cart routing. Otherembodiments of this aspect include corresponding computer systems,apparatus, and computer programs recorded on one or more computerstorage devices, each configured to perform the actions of the methods.

Other embodiments of one or more of these aspects include correspondingsystems, apparatus, and computer programs, configured to perform theactions of the methods, encoded on computer storage devices.

It should be understood that the language used in the present disclosurehas been principally selected for readability and instructionalpurposes, and not to limit the scope of the subject matter disclosedherein.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure is illustrated by way of example, and not by way oflimitation in the figures of the accompanying drawings in which likereference numerals are used to refer to similar elements.

FIG. 1 is a block diagram of an example system and data communicationflow for a hybrid modular storage fetching system.

FIG. 2 is a flowchart of an example method for picking an order in ahybrid modular storage fetching system.

FIG. 3A is a schematic of an example configuration of a distributionfacility layout in a hybrid modular storage fetching system.

FIG. 3B is an illustration of an example pick-cell station.

FIG. 4A is a flowchart of an example method for receiving and routingorder data.

FIG. 4B is a flowchart of an example method for picking pick-to-cartitems using a cart automated guided vehicle.

FIG. 4C is a flowchart of an example method for retrieving items inmodular storage units from a high-density storage area using a modularstorage fetching automated guided vehicle.

FIG. 4D is a flowchart of an example method for combining items fromdifferent zones of the distribution facility at a pick-cell station.

FIGS. 5A and 5B are illustrations of an example cart automated guidedvehicles.

FIGS. 6A-6B are illustrations of example modular storage units.

FIGS. 7A-7I are illustrations of example modular storage fetchingautomated guided vehicles.

DESCRIPTION

Among other benefits, the technology described herein improves upon thatdescribed in the Background Section. For instance, the technologyprovides robotic devices, systems, methods, and other aspects that canmore efficiently process goods (e.g., items or items in a distributionfacility) based on demand. Further, the technology can reduce the amountof irrelevant items carried simultaneously with relevant items byproviding automated guided vehicle(s) (AGV(s)) that are configured toefficiently carry items.

With reference to the figures, reference numbers may be used to refer tocomponents found in any of the figures, regardless whether thosereference numbers are shown in the figure being described. Further,where a reference number includes a letter referring to one of multiplesimilar components (e.g., component 000 a, 000 b, and 000 n), thereference number may be used without the letter to refer to one or allof the similar components.

The technology described herein can be integrated into any logisticssystem, dispatch system 106, warehouse execution system 102, warehousemanagement system 104, etc., to coordinate the provision of to-be-pickeditems in a hybrid modular storage fetching system. This technologybeneficially improves productivity and throughput, increases assetutilization, and lowers cycle time and labor costs. These benefits, inturn, lead to shorter delivery times and result in significant savingsand business value.

FIG. 1 depicts an example system 100 and data communication flow forimplementing a hybrid modular storage fetching system. The system 100includes a warehouse execution system (WES) 102. The WES 102 is coupledto equipment 110 (e.g., conveyor controls, conveyor scanners, conveyors,automated induction equipment, other warehouse equipment, etc.), awarehouse management system (WMS) 104, a data store 120 storingwarehouse management, execution, dispatch, picking, carton, order, item,AGV, map, and/or other data, a picking system 108 (e.g., pick-to-voice,pick-to-light, etc.), and a dispatch system 106.

The WES 102 may, in some embodiments, include one or more hardwareand/or virtual servers programmed to perform the operations, acts,and/or functionality described herein. For instance, the WES 102 mayinclude an AGV management engine and a SKU routing engine. Thesecomponents may comprise software routines storable in one or morenon-transitory memory devices and executable by one or more computerprocessors of the WES 102 to carry out the operations, acts, and/orfunctionality described herein. In further embodiments, these routines,or a portion thereof, may be embodied in electrical hardware that isoperable to carry out the operations, acts, and/or functionalitydescribed herein.

The AGV management engine is executable to generate a schedule thatdefines the route for an AGV during a picking session, as describedherein. For a given cart AGV 116 a . . . 116 n, depending on the items(e.g., identified by stock keeping units or SKUS) to be placed in thecartons of that cart, the AGV management engine generates a schedule andtransmits it to the dispatch system 106, which in turn deploys a cartAGV 116 according to the schedule, for instance. In someimplementations, the dispatch system 106 instructs the AGV to proceedthrough one or more of the picking zones of the distribution facilityaccording to the schedule. The schedule of each of the AGVs may becoordinated such that an optimal flow can be achieved, as discussedelsewhere herein.

The SKU (e.g., a stock keeping unit or unique identifier identifying anitem) routing engine is executable to route items into different storagezones depending based on picking profiles of the items, which may bestored and maintained as item data 130. The SKU routing enginedynamically monitors the picking activity in the distribution facility,tracks which items have the highest volume or velocity for a giventimeframe, stores the tracking data in the data store 120, and caninstruct the AGV management engine to have items relocated by AGVs todifferent storage locations in the distribution facility based on thetracked picking activity.

A picking profile of a given item can change over time as demand for theitem changes. The demand for a given item may be random or predicable(e.g., seasonal), and may change based on time of day, week, month,year, etc. The item routing engine may maintain the picking profile inthe database as item data 130, and utilize that data to determine inwhich zone of the distribution facility to store the item.

Advantageously, based on the picking profiles (e.g., velocity andvolume), the SKU routing engine may provide a distinct automatedapplication for picking. In some implementations, the SKU routing enginemay continually algorithmically evaluate the picking profile of each SKUand instruct the WES 102 and dispatch system 106 to transfer/relocateitems to another storage location and/or picking area, swap itemlocations, etc., when necessary to maintain the most expedient flow inthe facility. This advantageously reduces capital associated with fullyautomated high velocity items and reduces replenishment complexity.

The WES 102 may store productivity information for points in thedistribution facility in a database (e.g., a non-transitory data store120). The productivity information may reflect mechanical capacity ofthat given point of the AGV system. In some cases, the mechanicalcapacity may be dynamic based on current conditions (e.g., systemhealth, staffing levels (e.g., number of associates working in zone),stock levels, operational state, etc.).

In some embodiments, the WMS 104 and/or WES 102 may algorithmicallyanalyze the configuration of a cart AGV 116 depending on items that areset for distribution/fulfillment in the next picking time window. TheWMS 104 and/or WES 102 may generate a stocking list for the cart basedon hub, priority, pick density, pick zone demand, and item-to-itemaffinity, etc. The AGV management engine may use the stocking list whengenerating the schedule for the cart AGV 116.

The dispatch system 106 may be electronically communicatively coupled toa plurality of AGVs. The dispatch system 106 includes hardware andsoftware configured to dispatch the AGVs, and is coupled forcommunication with the WES 102 and WMS 104 to receive instructions andprovide data. The dispatch system 106 calculates a route to execute thetask considering traffic and resources. In some cases it adjusts theroute or the task in order to keep the route optimum.

The AGVs are robotic vehicles including drive units providing motiveforce for moving the AGVs (and, in some instances, carts, modularstorage units 602, etc.), guidance systems for determining position ofthe AGVs within the distribution facility, and equipment for carryingitems. The equipment for carrying items may include carton holders ormodular storage unit holders (e.g., carts, shelves, etc.), for example,as described in further detail in reference to FIGS. 5A-7I. FIGS. 5A-7Idepict types of AGVs, such as modular storage fetching (MSF) AGVs 114and cart AGVs 116.

A cart AGV 116 is an automated guided vehicle or robot configured toautonomously transport pick-to-cart items from a pick-to-cart area 302of the distribution facility to a pick-cell station 316 and/orfinalizing area 314 (e.g., as described in reference to FIG. 3A). Thecart AGV 116 may include a drive unit adapted to provide motive force tothe cart AGV 116 and a guidance system adapted to locate the cart AGV116 in the distribution facility. In some implementations, the cart AGV116 is adapted to autonomously transport a carton holder (e.g., a cartor shelves) that is, in turn, adapted to hold cartons. Cartons mayinclude, for instance, a box (e.g., a shipping box) adapted to holditems. For example, a cart AGV 116 may push/pull a cart (e.g., a cartonholder) holding cartons around a pick-to-cart area 302 and mayautomatically stop at storage bays of the pick-to-cart area 302 whereitems to be picked are stored, so that a picker in the pick-to-cart area302 can easily place items into one or more of the cartons. In someinstances, the cart AGV 116 may transport the cart to a pick-cellstation 316 to receive additional items into the cartons fromhigh-density storage (e.g., from modular storage units 602 inhigh-density storage, as described below). In some instances, the cartAGV 116 may move at walking speed next to, behind, or in front of apicker walking through the pick-to-cart area 302 of the distributionfacility. Additional details of example cart AGVs 116 are shown inreference to FIGS. 5A and 5B.

An MSF AGV 114 a . . . 114 n is an automated guided vehicle or robotconfigured to autonomously transport items from a high-density storagearea 304 of the distribution facility to a pick-cell station 316,replenishment area 318, and/or finalizing area 314. The MSF AGV 114 mayinclude a drive unit adapted to provide motive force to the MSF AGV 114,a guidance system adapted to locate the MSF AGV 114 in the distributionfacility, and a modular storage unit holder adapted to hold modularstorage units 602. In some implementations, an MSF AGV 114 mayautonomously retrieve modular storage unit(s) 602 containing items to bepicked in an order. For instance, the MSF AGV 114 may transport themodular storage unit(s) 602 to a pick-cell station 316, so that a pickerat the pick-cell station 316 can pick items from the modular storageunit(s) 602 and place them into cartons in a cart. For example, a cartAGV 116 may transport a carton to a bay in the pick-to-cart area 302having a first item in an order, then to a pick-cell station 316 where aseparate MSF AGV 114 has delivered or will deliver a second item (e.g.,in a modular storage unit 602) in the order, so that a picker can placethe second item into the carton with the first item. The system maycoordinate the timing, placement, and movement of the cartons, modularstorage units 602, pick-cell station 316 workload, and AGVs to bringcartons and modular storage units 602 having items corresponding to anorder to the same pick-cell station 316 during the same time window, asdescribed in further detail herein. Additional details of example MSFAGVs 114 are described in reference to FIGS. 7A-7I.

The WMS 104 may, in some embodiments, include one or more hardwareand/or virtual servers or software routines storable in one or morenon-transitory memory devices and executable by one or more processorsto perform the operations, acts, and/or functionality described herein.The WMS 104 may be configured to store and maintain carton data 124 inthe data store 120. The carton data 124 includes information aboutcartons in the system, such as a unique identifier for each carton, acarton type, the zones the carton will visit, the number of pick linesthe carton proceed through, and the priority for the carton. Somecartons may have a higher priority relative to other cartons and thesystem may expedite handling of those cartons with higher priorityrelative to other cartons in the system. The carton data 124 may includea picklist defining the items the carton will contain. The WMS 104 maystore data mapping items to the different pick zones (e.g., thepick-to-cart area 302, the high-density storage area 304, a particularmodular storage unit 602, a particular location at a particularpick-cell station 316, etc.). In some implementations, the WMS 104 maybe configured to communicate the carton data 124 with the WES 102, thepicking system 108, and/or dispatch system 106 in real time, in batches,as requested by these components, etc.

The picking system 108 may, in some embodiments, include one or morehardware and/or virtual servers or software routines storable in one ormore non-transitory memory devices and executable by one or moreprocessors to perform the operations, acts, and/or functionalitydescribed herein. The picking system 108 may receive pick confirmations,for example, from pickers or operators (e.g., using barcode scanners,NFC, RFID chips, or other sensors or input methods) working within apick zone (e.g., a pick-to-cart area 302, pick-cell station 316, etc.)confirming that picks for a given carton have been performed, asdescribed in further detail below. An example picking system 108 mayinclude an available pick-to-voice or a pick-to-light system. Thepicking system 108 may be configured to communicate the pickconfirmation data with the WES 102, WMS 104, or other components of thesystem in real time, in batches, as requested by the components of thesystem, etc.

The picking system 108 may receive confirmatory input (e.g., pickconfirmations) from pickers working within a pick zone. The confirmatoryinput confirms that all picks for a given carton have been completed.The picking system 108 transmits the confirmatory input to the WES 102.The confirmatory input may include the time stamp reflecting completionof the picks in the zone, a unique identifier identifying the picker(operator), a unique identifier identifying the pick zone, a uniqueidentifier identifying the AGV, and/or a unique identifier identifyingthe carton (e.g. a carton number).

The data store 120 is an information source for storing and providingaccess to data. The data stored by the data store 120 may be organizedand queried using various criteria including any type of data stored byit. The data store 120 may include data tables, databases, or otherorganized collections of data. An example of the types of data stored bythe data store 120 may include, but is not limited to map data 122, AGVdata 128, carton data 124, order data 126, modular storage unit data,etc. In some instances, the data store 120 may also include, conveyingsystem attributes, picking data, picker attributes, sensor data, etc.

The data store 120 may be included in the WES 102, WMS 104, or inanother computing system and/or storage system distinct from but coupledto or accessible by the WES 102, WMS 104, or other components of thesystem 100. The WES 102, picking system 108, and/or dispatch system 106,for example, may store and maintain map data 122, order data 126, cartondata 124, and AGV data 128. The data store 120 can include one or morenon-transitory computer-readable mediums for storing the data. In someimplementations, the data store 120 may store data associated with adatabase management system (DBMS) operable on a computing system. Forexample, the DBMS could include a structured query language (SQL) DBMS,a NoSQL DMBS, various combinations thereof, etc. In some instances, theDBMS may store data in multi-dimensional tables comprised of rows andcolumns, and manipulate, e.g., insert, query, update and/or delete, rowsof data using programmatic operations.

The map data 122 may include data reflecting the 2 or 3 dimensionallayout of the facility including the location of modular storage units602, picking areas, lanes, equipment 110, etc. Map data 122 may indicatethe attributes of the distribution facility, including attributes ofzones (e.g., one or more pick-to-cart areas 302, high-density storageareas 304, induction zones 308, finalizing areas 314, pick-cell stations316, replenish stations, etc.). For example, attributes of zones mayinclude the number, quantity, and location of shelving units or bays,modular storage units 602, items, guidance system locators, etc. In someimplementations, the map data 122 may include the location of guidancesystem locators.

The order data 126 includes data about picking including orders, itemspicked, items to be picked, picking performance, picker identities, pickconfirmations, locations items are picked from, etc. Order data 126 mayindicate the quantity and identity of items in orders, shippingaddresses, order priority, progress of order fulfillment, number ofcartons in an order, etc.

Item data 130 may describe items available for picking in a distributionfacility. The item data 130 may include unique identifiers for theseitems, the item volume (e.g., the total amount picked in given window(e.g., in an hour, day, etc.)), the item velocity (e.g., number ofdifferent times item picked in given window (e.g., per hour, day etc.),the unique location of the items within the distribution facility (isle,shelf, shelf position, etc.), other attributes of the item (e.g., size,description, weight, quantity of items in a package, color, etc.), iteminventory, mapping of items of modular storage units 602, etc. In someimplementations, the item data 130 may include the quantity ofparticular items a modular storage unit 602 contains, the currentlocation of a modular storage unit 602, a preferred storage location ofitems and/or modular storage units 602, a threshold inventory level ofitems to be satisfied before autonomously transporting the modularstorage unit 602 to a replenishment area 318 by an MSF AGV 114 (e.g., torestock the items in the modular storage unit 602).

The AGV data 128 may describe the state of an AGV (operational state,health, location, battery life, storage capacity, items being carried,cartons, etc.), whether picker assigned to it, etc.

The components of the system may be coupled to exchange data viawireless and/or wired data connections. The connections may be made viadirect data connections and/or a computer network. The computer networkmay comprise any number of networks and/or types of networks, such aswide area networks, local area networks, virtual private networks,cellular networks, close or micro proximity networks (e.g., Bluetooth,NFC, etc.), etc. In some embodiments, one or more of these componentsmay be coupled via a data communications bus.

FIG. 2 is a flowchart of an example method for picking an order in ahybrid modular storage fetching system. At 202, the WES 102 may generatea picking schedule including pick-to-cart routing, modular storagefetching (MSF) routing, and/or pick-cell routing based on order data126. The order data 126 may include one or more first uniqueidentification codes representing one or more first items located in apick-to-cart area 302 of a distribution facility. In some instances, theorder data 126 may also include one or more second unique identificationcodes representing one or more second items located in a high-densitystorage area 304 of the fulfilment facility.

The pick-to-cart routing describes routing of a particular cart AGV 116a . . . 116 n through a pick-to-cart area 302. For example, thepick-to-cart routing may include a picking list of pick-to-cart items tobe picked to the cartons transported by the cart AGV 116. Thepick-to-cart routing may indicate the location of the storage units,shelves, or bays in which an item in the picking list is located. Insome implementations, the pick-to-cart routing may also include adefined route of a cart AGV 116 through these locations and anindication of locations at which to stop the cart AGV 116, so that apicker can pick items from adjacent storage units, shelves, or bays intothe cartons transported by the cart AGV 116. The pick-to-cart routingmay also include a schedule indicating when to pick items and when todeliver cartons to a particular pick-cell station 316.

The MSF routing describes routing of a particular MSF AGV 114 through ahigh-density storage area 304. For example, the MSF routing may includea picking list of items stored in modular storage units 602, uniqueidentification codes of the modular storage units 602, and the currentlocations of the modular storage units 602. In some instances, thecurrent location of the modular storage units 602 may be in thehigh-density storage area 304, in a replenishment area 318, or at apick-cell station 316. The MSF routing may also include a defined routeof an MSF AGV 114 through the distribution facility to retrieve one ormore modular storage units 602 including items from one or more ordersand deliver those modular storage units 602 to assigned pick-cellstations 316. The defined route may be calculated to most efficientlyretrieve one or a series of modular storage units 602, maximize aquantity of modular storage units 602 for the MSF AGV 114 to retrieve ina single trip, to avoid traffic of other AGVs, and/or to cause themodular storage unit(s) 602 to arrive at a pick-cell station 316 at aminimized time difference from a carton (e.g., transported by a separatecart AGV 116) arriving at the same pick-cell station 316 to which theitem in the modular storage unit 602 is to be placed, for example. TheMSF routing may also include a schedule indicating when to retrievemodular storage units 602 and when to deliver the modular storage units602 to a particular pick-cell station 316.

Pick-cell routing may describe routing of AGVs among pick-cell stations316. For instance, a modular storage unit 602 may be transferred by anMSF AGV 114 from one pick-cell station 316 to another pick-cell station316, as described elsewhere herein.

In some implementations, the WES 102 may determine, based on loadinformation in one or more of the pick zones, that a particular zone,picker, path, pick-cell station 316, etc., has a high traffic load. Inresponse to such a determination, the WES 102 may dynamically adjust therouting schedule, for example, dictating which cart AGVs 114 or MSF AGVs116 are sent into different zones of the distribution facility. Forexample, the WES 102 may determine that there is a threshold level oftraffic (e.g., by cart AGVs 114) in the pick-to-cart area 302, inresponse to which determination, the WES 102 may induct AGVs (e.g., cartAGVs 114 with particular orders to be filled) into the hybrid modularstorage fetching system that bypass the pick-to-cart area 302 andproceed directly to pick-cell stations 316 to receive items from modularstorage units 602. In another example implementation, the WES 102 maydetermine, for instance, that there is a threshold level of traffic in astaging area 312 or that no MSF AGVs 116 are available to retrieve itemsfrom high-density storage 304 and may, in response, induct cart AGVsinto the system that do not stop at a pick-cell station 316 or thatrequire fewer modular storage units 602 to be retrieved fromhigh-density storage. Accordingly, in some implementations, the WES mydynamically balance the load of various zones, AGVs, pick-cell stations,etc., in the system by adapting the composition (e.g., items frompick-to-cart versus from high-density storage) of orders/cartons on aparticular AGV (e.g., a cart AGV), for example.

At 204, the WES 102 or picking system 108 may transmit a signalincluding the picking schedule (or components thereof) to thedispatching system 106.

At 206, the dispatching system 106 may dispatch a cart AGV 116 accordingto the picking schedule. In some implementations, dispatching a cart AGV116 may include creating cartons, assigning the cartons to a cart to betransported by a cart AGV 116, placing the cartons on the cart, and, insome instances, coupling the cart AGV 116 with the cart. For instance,the WES 102 may assign orders (or items thereof) to cartons. Labels withunique identification codes identifying the cartons may be printed,placed on cartons, and the cartons may be placed on the cart at aninduction area 308. The unique identification codes of the cartons maymatch, in the data store 120, the carton (and therefor the cart/cart AGV116) with items to be picked.

At 208, the dispatching system 106 may dispatch an MSF AGV 114 accordingto the MSF routing.

At 210, the cart AGV 116 may autonomously navigate along a path throughthe pick-to-cart area 302 according to the pick-to-cart routing toretrieve one or more items located in the pick-to-cart area 302. Asdescribed elsewhere herein, the cart AGV 116 may follow the guidancesystem through the pick-to-cart area 302 and stop at designated areasfor items stored in those areas to be picked to the designated cartons.In some implementations, the cart, carton, cart AGV 116, storage area,or separate computing device (e.g., a mobile device of a picker) mayinclude an output device provide output indicating items to be picked ata particular location and, in some implementations, the output devicemay also include an input to receive pick confirmations. Once the pickconfirmation has been received, the cart AGV 116 may autonomously moveto the next area to pick a subsequent item assigned to a carton on thecart.

Once items in the pick-to-cart storage area have been picked to the cartAGV 116, the cart AGV 116 may autonomously navigate to an assignedpick-cell station 316 or to a finalizing area 314 according to thepick-to-cart routing. In some implementations, the cart AGV 116 maydecouple from the cart and leave the cart at the pick-cell station 316(or at a finalizing area 314) so that the cart AGV 116 may transportanother cart while the first cart is being filled with items frommodular storage units 602, for example.

At 212, the MSF AGV 114 may autonomously navigate to a location of theone or more modular storage units 602 in the high-density storage area304 (or a replenishment area 318, pick-cell station 316, etc.), the oneor more modular storage units 602 containing one or more items in anorder, for example, an order with a carton transported by a cart AGV116, as described above. The MSF AGV 114 may autonomously retrieve theone or more modular storage units 602 from the high-density storage area304, for example. The MSF AGV 114 may then autonomously navigate fromthe location of the modular storage unit(s) 602 to the pick-cell station316 according to the MSF routing to transport the modular storageunit(s) 602 to the pick-cell station 316. In some implementations, theMSF AGV 114 may hold a plurality of modular storage units 602 and maydeliver each of the modular storage units 602 to the same pick-cellstation 316 or to separate pick-cell stations 316. In someimplementations, the MSF AGV 114 may also retrieve modular storage units602 that are no longer needed at a particular pick-cell station eitherseparately or while delivering new modular storage units 602 to thepick-cell station.

At 214, the picking system 108 outputs instructions to an output device(e.g., on the cart, pick-cell station, modular storage unit 602, orseparate computing device, etc.), the instructions directing a picker ata pick-cell station to transfer items from modular storage unit(s) 602at the pick-cell station to carton(s) on the cart.

FIG. 3A depicts a schematic of an example configuration of adistribution facility. It should be understood that various distributionfacilities may include different picking zones having different stockinginfrastructure and picking configurations. For instance, high-volumeand/or velocity items (e.g., items appearing frequently in orders) maybe stored in a pick-to-cart area 302 and be available for immediatepicking, and relatively moderate and/or low-volume and/or velocity itemsmay be stored in higher-density storage area 304 on modular storageunits 602 which may be retrieved by MSF AGVs 114 for an upcoming pick.

The layout depicted in FIG. 3A includes various areas: an induction area308, a pick-to-cart area 302, a pick-cell area 310, a pick-cell stagingarea 312, a high-density storage area 304, a finalizing area 314, and anelevator for multi-level access (not shown). In some cases the layoutmay include multiple levels of mezzanine with one or more of thedifferent zones/areas. In some implementation, cart AGVs 116 are stagedin the induction area 308 and are set up for picking sessions. In someembodiments, cartons are assembled, labeled with unique scannable visualidentifiers to associate them with specific orders, and are placed onthe supports (e.g., cart shelves) of the cart AGVs 116 in the inductionarea 308.

The pick-to-cart area 302 is configured for high-velocity and/or volumeitems and advantageously reduces capital associated to handle this typeof item class. Inventory may be stored in high-volume storage in cartonsor pallets, for example. High velocity items may be divided into pickzones, each zone may include a plurality of bays (e.g., 4, 5, 6+), whichmay be balanced by the SKU routing engine based on demand by the SKUrouting engine. Cart AGVs 116 may be scheduled by the AGV managementengine to autonomously visit these zones, and pickers accompanying thecart AGVs 116 may be guided by the picking hardware (e.g., pick-to-voiceand/or pick-to-light) controlled by the picking system 108. In anexample, a cart AGV 116 is instructed by the AGV management system tostop directly in front of a bay location. The cart AGV 116 mayself-locate using a guidance system. For example, the guidance systemmay include guidance system locators, such as guide tape (magnetic,colored, etc.), laser target navigation, inertial navigation, visionguidance, geolocation, QR codes on the floor of the distributionfacility, RFID (radio frequency identification) tags, beacons, etc.,that can be used to locate and navigate AGVs in the distributionfacility. Further, the AGVs may include guidance system componentsconfigured to read the guidance system locators, such as a QR codereader, wireless radio, etc.

After the picker picks the item and confirms the pick with the pickinghardware, the cart AGV 116 autonomously moves to the next sequential bayuntil the picks are complete. As shown in FIG. 3A, a cart AGV 116 hasthe capability to bypass zones, bays, shelves, etc., without picks. Eachzone can have dedicated cart AGV 116 accumulation before the zone toreduce cycle time.

The picking station area may include pick-cell stations 316 a, 316 b,and 316 c situated along primary path(s) via which the cart AGVs 116 arerouted. In FIG. 3A, the pick-cell stations 316 are situated opposing aportion of the pick-to-cart area 302 and the cart AGVs 116 may be routedto visit one or more of these pick-cell stations 316 depending on theitems that need to be picked and placed in the cartons of these cartAGVs 116. In the case that in given cart AGV 116 does not require anyitems from the picking station area, it may bypass it entirely andproceed to the finalizing area 314.

In some embodiments, for a given picking session, the AGV managementengine may establish a single line picking configuration in which thepicker and the cart travel through an inventory pick path along a singleline until the picks are fulfilled. In further embodiments, based ondemand, a fast moving area may be established by the AGV managementengine that includes multiple routes: a higher speed line that includessingle line picking for low-demand items and another area for highdemand items. This combination can advantageously balance daily labor.

The layout may also include a replenishment area 318 in which modularstorage units 602 are replenished with items. For instance, iteminventory in a given modular storage unit 602 may be replenished by aMSF AGV 114 that picks the modular storage unit 602 from static shelvesand transports them to the replenishment area 318 where a case may beopened and items from the case placed directly into the modular storageunits 602. One or more different items can be placed in a given modularstorage unit 602. In some cases the modular storage unit 602 may bereplenished while the container is in the static shelf. Having multipleoptions (manual or AGV) for replenishment has more flexibility to adjustto resource allocation and schedule. Additionally or alternatively, theMSF AGV 114 can swap out the modular storage unit 602 with anothercontaining the same SKUs which has been prepared ahead of time andstaged for that purpose.

In some implementations, the AGV management engine may instruct MSF AGVs114 to replenish and distribute modular storage units 602 in differentlocations of the high-density storage area 304 based on order history.In these implementations, items with high order frequency orders may bedistributed in more locations than items with lower order frequency. TheWES 102 may maintain a moving minimum based on order quantity minimizingthe need to use inventory from two locations to fulfill an order, andthe AGV management engine may schedule the AGVs accordingly.

The modular storage units 602 storing items may be moved by MSF AGVs 114from high-density storage area 304 into a staging area 312 and stagedfor movement into a pick-cell station for an upcoming pick. In someembodiments, the storage units of faster-moving items may be moveddirected to a pick cell 382 in a given pick-cell station 316.

In further embodiments, the AGV management engine may instruct a MSF AGV114 to transfer a modular storage unit 602 between cells of a pick-cellstation 316, or between pick-cell stations 316 (e.g., 316 a and 316 b)without having to expend the time to return the modular storage unit 602to the high-density storage area 304.

FIG. 3A also illustrates example paths of AGVs through the distributionfacility. The paths are represented by dotted lines, cart AGVs 116 arerepresented by ovals, and MSF AGVs 114 a . . . 114 d are represented bydiamonds.

Example cart AGV paths are illustrated in FIG. 3A, for example, a cartAGV 116 may navigate from an induction area 308, on a path through thepick-to-cart area 302, and then to one or more pick-cell stations 316.Once the picks for the cart AGV 116 have been completed, it may navigateto a finalizing area 314 where cartons are prepared for shipment, forexample. Once the cartons have been removed from the cart AGV 116, thecart AGV 116 may return to the induction area 308 to start through theprocess again.

Example MSF AGV paths are also illustrated in FIG. 3A, for example, anMSF AGV 114 a may transport a modular storage unit E from a firstpick-cell station 316 a to a replenishment area 318 for replenishment.An MSF AGV 114 b may retrieve a first modular storage unit A from afirst location, navigate to a second location, retrieve a second modularstorage unit B, and transport both the first and second modular storageunits A and B to a pick-cell station 316 b. An MSF AGV 114 c mayretrieve a modular storage unit C from a first pick-cell station 316 aand transport it to a second pick-cell station 316 b. An MSF AGV 114 dmay retrieve a modular storage unit D and transport it back to thehigh-density storage area 304. It should be understood that these pathsand implementations are provided as examples and that other combinationsare possible and contemplated herein. For example, one or more MSF AGVs114 may perform some or all of the paths illustrated as well as othersnot illustrated in FIG. 3A. Further, as described elsewhere herein, theautomation of the MSF AGV 114 may be performed in synchronization withother actions (e.g., automation of cart AGVs 116, picking sessions orwindows, movement of other AGVs or pickers, etc.) in the hybrid modularstorage fetching system.

FIG. 3B is an illustration of an example pick-cell station 316. Eachpick-cell station 316 may include one or more pick cells 384. The pickcells 382 are a temporary storage mediums (e.g., shelves, bays, etc.)for the modular storage units 602 (e.g., mini pallets, totes, modularstorage racks, etc.) and modular storage units 602 are storagecontainers that can be picked up or tugged and transported by a MSF AGV114. In some cases the pick-cell station 316 may include an outputdevice, such as a pick-to-light frame, for carts, that matches thelocations of the cartons in the cart and/or a pick-to-light frame 384for the pick cells 382 to indicate the locations of modular storageunits 602 to use for a particular pick. For instance, a pick-cellstation 316 may include an output device configured to provide pickinginstructions to a picker, the picking instructions indicating to thepicker which of the items in the modular storage units 602 to place in acarton held on the carton holder of the cart AGV 116.

One or multiple of the pick cells 382 may be organized into a stagingarea 312 around a picker in a pick-cell station 316, so that modularstorage units 602 can be easily accessed by the picker. In someimplementations, an MSF AGV 114 may be configured to stage the modularstorage units 602 at the staging area 312. For instance, an MSF AGV 114may approach from the rear of a pick cell 382 and stage (e.g., place,deliver, etc.) a modular storage unit 602 on the pick cell 382. In someimplementations, a modular storage unit 602 may be associated by thepicking system 108 with a particular location in the staging area 312 tomore precisely direct a picker to the location of the modular storageunit 602 (e.g., using a pick-to-light or other output system).

In some implementations, a pick cell 382 may be a device that is mobileand can be transported by an AGV. A mobile pick cell 382 can bepreconfigured with modular storage units 602 prior to picking and thentransported to the station.

At a given pick-cell station 316, a cart AGV 116 may arrive and situateitself on one side of the station with the cartons facing the picker. Onthe other sides of the station are pick cells 382 in which modularstorage units 602 situated and from which the picker may select items tofulfill the orders associated with the cartons. The modular storageunits 602 may contain one or more items, types of items, etc.

FIGS. 4A-4D are example methods for fulfilling an order in a hybridmodular storage fetching system. FIG. 4A is a flowchart of an examplemethod for receiving and routing order data 126. At 402, the WES 102 mayreceive an order including items for distribution/fulfillment. The ordermay be reflected in order data 126 having a unique identification code(e.g., unique product codes, stock keeping units, etc.) for an item anda quantity associated with that item. The order may be assigned a carton(e.g., of a particular size, dimension, etc.) for picking and/orshipping or, in some instances, split into multiple cartons.

At 404, the WES 102 may analyze the order to determine whether the orderincludes items in pick-to-cart 302 and/or high-density storage areas304. For example, a unique identification code of the items in the ordermay be matched against information in the data store 120 to evaluate thelocation (e.g., the particular zone, bay, shelf, modular storage unit602, etc.) and quantity of the item in the inventory of the distributionfacility.

At 406, the WES 102 may generate a picking schedule includingpick-to-cart, MSF, and/or pick-cell routing, as described above. Thegenerated picking schedule may indicate timing, a particular cart AGV116 to retrieve pick-to-cart items, a particular MSF AGV 114 to retrieveitems in high-density storage, and a particular pick-cell station 316 inwhich the items from each zone may be combined in a carton. In someimplementations, the picking schedule may also indicate an inductionstation, finalizing area 314, particular path through the distributionfacility, particular pickers or operators assigned to the orders, etc.

At 408, the dispatching system 106 may transmit a signal identifyingpick-to-cart items, item locations, and, in some implementations,identification of a designated pick-cell station 316 and time window forthe items to be at the designated pick-cell station 316, to a cart AGV116. It should be noted that other information, such as routingdirections, priority, traffic of other AGVs, etc., may also be providedto the cart AGV 116 and/or a computing device of picker(s) associatedwith the cart AGV 116 to refine the routing and autonomous navigation ofthe cart AGV 116.

At 410, the dispatching system 106 may transmit a signal identifyinghigh-density items, corresponding modular storage units 602, locationsof the corresponding modular storage units 602, etc., to one or more MSFAGVs 114 (e.g., multiple MSF AGVs 114 may be employed to distribute thework of modular storage unit 602 transport). Other information such asidentification of a designated pick-cell station 316 and time window forthe items to be at the designated pick-cell station 316, routingdirections, priority, traffic of other AGVs, modular storage unit 602dimensions, etc., may also be transmitted in the signal to the MSFAGV(s) 114.

FIG. 4B is a flowchart of an example method for picking pick-to-cartitems using a cart AGV 116. At 422, the WES 102 may assign items tocarton(s) and associate the cartons with a cart in the database, and at424, the dispatch system 106 may dispatch a cart AGV 116 with the cartto a pick-to-cart area 302, for example, as described above.

At 426, the cart AGV 116 may navigate to a bay (e.g., a shelving bay)where a pick-to-cart item is stored. The cart AGV 116 may stop adjacent(e.g., in front of) to the location where the item is stored.

At 428, the picking system 108 may output an instruction to an outputdevice of a picker identifying the item and quantity to be picked atthat location. In some implementations, the picking system 108 maycoordinate lights or screens on the cart indicating into which carton anitem is to be placed and/or lights on a shelving bay/location of theitem in the pick-to-cart area 302 indicating the storage location of theitem. Other systems, such as audio (e.g., pick-to-voice), a mobilecomputing device indicating the location of the item, etc., arepossible.

At 430, the picking system 108 and/or cart AGV 116 may determine whetherthere are additional items in the pick-to-cart area 302 assigned to thecart and, in response to determining that there is an additional item,may return to 426 to navigate to the next location of an item. In someimplementations, the order of locations visited by the cart AGV 116 isbased on a picking list configured to order the picking according to adesignated path through the pick-to-cart area 302. In someimplementations, the output, at 428, may indicate that an item at agiven location is to be picked into multiple cartons (e.g., whichcartons may correspond to separate orders) on the cart.

At 432, in response to a negative determination at 403, the pickingsystem 108 may determine whether there are items in the high-densitystorage area 304 also assigned to one or more cartons transported by thecart AGV 116 (and/or whether the cart is scheduled to be delivered to apick-cell station 316). If there are no items to be added to the cartonsfrom the high-density storage area 304 (or if, for example, these itemsare to be added at the finalizing area 314), the cart AGV 116 mayautonomously navigate to a finalizing area 314. If, however, there areadditional items to be added to one or more of the cartons transportedby the cart AGV 116 at a pick-cell station 316, the cart AGV 116 mayautonomously navigate to an assigned pick-cell station 316 to receivethose items. This may be done according to (e.g., at a time window setby) a picking schedule, in coordination with an availability at thepick-cell station 316, and/or in coordination with one or more MSF AGVs114 delivering items to the assigned pick-cell station 316 to be pickedinto cartons on the cart AGV 116.

FIG. 4C is a flowchart of an example method for retrieving items inmodular storage units 602 from a high-density storage area 304 using anMSF AGV 114. The method depicted in FIG. 4C may be executed incoordination with the method depicted in 4B, for example, as describedelsewhere herein.

At 442, the WES 102 may identify a location of a first modular storageunit 602 having an appropriate quantity of first items in response toreceiving a signal to retrieve those items from high-density storage (oranother current location of a modular storage unit 602, such as apick-cell station 316, replenishment area 318, etc.). As describedabove, the quantity of particular items stored in a modular storage unit602 and the current location (and, in some instances, schedule of futurelocations) of the modular storage unit 602 are stored in the data store120. In some implementations, a particular carton, order, or pluralityof orders assigned to a cart may require multiple of a particular item.The WES 102 may verify that a sufficient quantity of the item is locatedin a particular modular storage unit 602 prior to signaling an MSF AGV114 to retrieve the particular modular storage unit 602. If a particularmodular storage unit 602 does not have a sufficient quantity of an itemto fill all designated cartons, the MSF AGV 114 may retrieve a differentmodular storage unit 602 (e.g., having a sufficient quantity of theitem), multiple modular storage units 602, or may send an error for areplenishment system/area, a human operator, or other system to remedythe error.

At 444, the WES 102 may identify a location of second modular storageunit(s) 602 having appropriate quantities of second item(s). A set ofcartons transported by a cart AGV 116 may include any number ofdifferent items to be retrieved from high-density storage by an MSF AGV114.

At 446, the MSF AGV(s) 114 (e.g., multiple MSF AGVs 114 may be used) mayautonomously navigate to a location of a first modular storage unit 602in a high density storage area, and at 448, the MSF AGV 114 may retrievethe first modular storage unit 602 (e.g., as described in reference toFIGS. 7A-7I).

At 450, an MSF AGV 114 may then autonomously navigate to a location of asecond modular storage unit 602 in the high-density storage area 304 andretrieve a second modular storage unit 602. The path of an MSF AGV 114may be determined to efficiently retrieve each modular storage unit 602.Additionally, the particular modular storage unit 602 (e.g., whenmultiple modular storage units 602 have a certain item) may be selectedbased on the most efficient location for the MSF AGV 114 to retrieveand/or proximity to an assigned pick-cell station 316.

At 454, the MSF AGV 114 may autonomously deliver the first modularstorage unit 602 to a pick-cell station assigned for the first modularstorage unit 602 and, at 456, the MSF AGV 114 may autonomously deliverthe second modular storage unit 602 to a pick-cell station 316 assignedfor the second modular storage unit 602. In some implementations, thepick-cell station 316 for the first and second modular storage units 602may be the same pick-cell station 316. In some implementations, thepick-cell stations 316 for the different storage units may be different.For example, an MSF AGV 114 may deliver a first modular storage unit 602to a first pick-cell station 316 and then autonomously navigate to asecond pick-cell station 316 to deliver the second modular storage unit602.

FIG. 4D is a flowchart of an example method for combining items fromdifferent zones of the distribution facility at a pick-cell station 316.Once the cart AGV 116 has transported the cartons to the pick-cellstation 316 and the MSF AGV(s) 114 have transported the modular storageunits 602 to the pick-cell station 316, the picking system 108 (oranother component) may output, at 462, instructions to an output deviceof a pick-cell station 316 indicating an item to transfer from a modularstorage unit 602 to a particular carton. In some implementations, theoutput device or another computing device may also receive confirmatoryinput indicating that the item has been placed in a designated carton.

At 464, the picking system 108 determines whether there are additionalitems from the modular storage units 602 at the pick-cell station 316assigned to a particular carton. If there are addition items to bepicked for a carton, the method may return to 462 for the next itemassigned to a carton. If there are no more items to be picked for aparticular carton, the picking system 108 may determine, at 466, whetherthere are additional items from modular storage units 602 assigned tothe set of cartons in the cart (e.g., brought by the cart AGV 116 to theparticular pick-cell station 316). If there are additional items foradditional cartons, the method returns to 462 for those cartons anditems and iterates accordingly. It should be noted that the order of thepicking, output, confirmation, etc. process, may be changed withoutdeparting from the scope of this disclosure.

If the picks for a set of cartons on a cart are complete, at 468, thecart AGV 116 may autonomously navigate to a finalizing area 314, forinstance, to ship the cartons.

The picking system 108, WES 102, or another component of the system 100may move one or more of the modular storage units 602 from the pick-cellstation 316. For example, at 470, a picking system 108 may determinewhether additional items from a particular modular storage unit 602 areassigned to the pick-cell station 316 in a subsequent picking window(e.g., for a subsequent cart AGV 116 arriving at the pick-cell station316). If the modular storage unit 602 (e.g., items remaining in themodular storage unit 602) will be used again at the pick-cell station316, the modular storage unit 602 may be left, at 472, at the pick-cellstation 316 for an additional pick window.

At 474, the WES 102 or picking system 108 may determine whether itemsfrom a particular modular storage unit 602 are assigned to a differentpick-cell station 316 in a subsequent pick window and, if so, at 476,may direct the MSF AGV 114 to retrieve the modular storage unit 602 fromthe current pick-cell station 316 and deliver it to the differentpick-cell station 316.

At 478, the MSF AGV 114 may retrieve one or more modular storage unit(s)602 from the pick-cell station 316, autonomously navigate to a locationin the high-density storage area 304, and store the modular storage unit602 at that location. The locations at which the modular storage units602 are stored may be determined based on availability, proximity to apick-cell area 310, proximity to frequently co-ordered items, frequencywith which the items in the modular storage units 602 are retrieved, orany other schema.

In some implementations, if all of a particular item in a modularstorage unit 602 have been picked from the modular storage unit 602(e.g., it is empty), then the MSF AGV 114 may autonomously deliver themodular storage unit 602 to a replenishment area 318.

FIGS. 5A and 5B are illustrations of example cart AGVs 502 a and 502 b(e.g., also referred to as 116). The example cart AGVs may include anautomated guided vehicle 502 or robot configured to autonomouslytransport pick-to-cart items, as described above. The cart AGV 502 mayinclude or be adapted to autonomously transport a carton holder 504 a or504 b (e.g., a cart or shelves) that is adapted to hold cartons (notshown in FIGS. 5A or 5B). For example, a cart AGV 502 may push/pull acart (e.g., a carton holder 504). In some implementations, a carton maybe a box placed on a shelf of the carton holder 504.

FIGS. 6A-6B are illustrations of example modular storage units 602 a and602 b. In some embodiments, the modular storage units 602 are containersor sets of containers that may be moved between storage shelves, pickcells 382, etc. Modular storage units 602 may have various heights andwidths (e.g., 2 to 24 inches high, and 1, 2, or 4 feet wide) and depthsequal to the depths of shelving units (e.g., 18 to 24 inches). Forexample, the modular storage units 602 may be sized and configured tohold items commonly stocked in a fulfillment or distribution facilitywhile also fitting onto standard shelves. A modular storage unit 602 mayinclude a holding structure (e.g., a pallet as in 6A or a container asin 6B) adapted to hold items. The holding structure may be adapted tointerface with a retrieval mechanism (e.g., a fork) of an MSF AGV 114.

As illustrated in FIG. 6A, a modular storage unit 602 a may comprise apallet or tote, which may be a holding container to support itemsdesigned to be picked up by an MSF AGV 114 using its retrievalmechanism. For example, a modular storage unit 602 a may include apallet and a holding structure that supports items designed to be pickedup by an AGV with forks. In some implementations, a pallet may bestackable. In some implementations, a pallet may be attachable to acontainer to form a modular storage unit 602 such as the exampledepicted in FIG. 6B.

FIG. 6B illustrates another example modular storage unit 602 b. Asillustrated, a modular storage unit may include sides 604 and one ormore divisions 608 dividing the modular storage unit 602 b into multiplecompartments. Further, in some implementations, a modular storage unit602 b may include a door 610, which may be opened and closed by a pickerto provide easy access to items stored in the compartments. In someimplementations, an MSF AGV 114 may automatically position the door 610toward the center of a pick-cell station 316 to allow access by apicker.

FIGS. 7A-7I are illustrations of example MSF AGVs 702 a, 702 b, 702 c,702 d, and 702 e (also referred to as 114 herein). FIGS. 7A and 7Billustrate a first example MSF AGV 702 a. In some implementations, theMSF AGV 702 a may have the capability to reach and retrieve differentsize of modular storage units 602 (e.g., pallets, totes, etc.) fromdifferent levels of static shelves. The MSF AGV 702 a may be equippedwith retrieval mechanism 704 adapted to interface with the holdingstructure of a modular storage unit 602 to retrieve a given modularstorage unit 602 from a modular storage unit support structure 722(e.g., a shelving unit, pick cell 382, or other support structure) and,in some implementations, place the modular storage unit 602 in a modularstorage unit holder 706 of the MSF AGV 702. For instance, the retrievalmechanism 704 may be adapted to extract the modular storage unit 602from a shelving unit (e.g., 722) and place of the modular storage unit602 into a new location (e.g., a pick cell).

The retrieval mechanism 704 may include an elevator mechanism 708 tolift the modular storage unit 602 to one or more levels of the modularstorage unit holder 706. The modular storage unit holder 706 may includeone or more bays, shelves, or containers configured to receive modularstorage units 602 in a single or various sizes. The retrieval mechanism704 may be adapted to place a given modular storage unit 602 in any ofthe plurality of bays.

In some implementations, the retrieval mechanism of a MSF AGV 702 mayinclude forks 712, such as those depicted in FIGS. 7C-7I, which aredesigned to engage with a corresponding support structure of the modularstorage unit 602 (e.g., a bottom surface, preformed indentation(s),preconfigured channel(s), other structures or formations, etc.). Forks712 can be made of any material, such as plastic or metal.

As illustrated in FIG. 7C-7F, the forks 712 may be attached to anelevator mechanism 708 and may be retractable, so the forks 712 may beplaced at any desired height and maneuvered underneath and to lift themodular storage unit 602 from a shelving unit (e.g., 722) duringextraction.

As illustrated in FIGS. 7D, 7G-7I, the retrieval mechanism of the MSFAGV may include a fork 712 coupled with the MSF AGV 702 and configuredto lift the given modular storage unit 602 and remove the given modularstorage unit 602 from the modular unit storage structure 722.

As illustrated in FIG. 7G-7I, the forks 712 may be attached to a roboticarm 716 a or 716 b and may be pivotable to extend underneath a modularstorage unit 602 in order to lift the modular storage unit 602.

It should be noted that the components described herein may be furtherdelineated or changed without departing from the techniques describedherein. For example, the processes described throughout this disclosuremay be performed by fewer, additional, or different components.

It should be understood that the methods described herein are providedby way of example, and that variations and combinations of thesemethods, as well as other methods, are contemplated. For example, insome embodiments, at least a portion of one or more of the methodsrepresent various segments of one or more larger methods and may beconcatenated or various steps of these methods may be combined toproduce other methods which are encompassed by the present disclosure.Additionally, it should be understood that various operations in themethods are iterative, and thus repeated as many times as necessarygenerate the results described herein. Further the ordering of theoperations in the methods is provided by way of example and it should beunderstood that various operations may occur earlier and/or later in themethod without departing from the scope thereof.

In the above description, for purposes of explanation, numerous specificdetails are set forth in order to provide a thorough understanding ofthe present disclosure. However, it should be understood that thetechnology described herein can be practiced without these specificdetails in various cases. Further, various systems, devices, andstructures are shown in block diagram form in order to avoid obscuringthe description. For instance, various embodiments are described ashaving particular hardware, software, and user interfaces. However, thepresent disclosure applies to any type of computing device that canreceive data and commands, and to any peripheral devices providingservices.

In some instances, various embodiments may be presented herein in termsof algorithms and symbolic representations of operations on data bitswithin a computer memory. An algorithm is here, and generally, conceivedto be a self-consistent set of operations leading to a desired result.The operations are those requiring physical manipulations of physicalquantities. Usually, though not necessarily, these quantities take theform of electrical or magnetic signals capable of being stored,transferred, combined, compared, and otherwise manipulated. It hasproven convenient at times, principally for reasons of common usage, torefer to these signals as bits, values, elements, symbols, characters,terms, numbers, or the like.

It should be borne in mind, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities. Unlessspecifically stated otherwise as apparent from the following discussion,it is appreciated that throughout this disclosure, discussions utilizingterms such as “processing,” “computing,” “calculating,” “determining,”“displaying,” or the like, refer to the action and methods of a computersystem that manipulates and transforms data represented as physical(electronic) quantities within the computer system's registers andmemories into other data similarly represented as physical quantitieswithin the computer system memories or registers or other suchinformation storage, transmission or display devices.

A data processing system suitable for storing and/or executing programcode, such as the computing system and/or devices discussed herein, mayinclude at least one processor coupled directly or indirectly to memoryelements through a system bus. The memory elements can include localmemory employed during actual execution of the program code, bulkstorage, and cache memories that provide temporary storage of at leastsome program code in order to reduce the number of times code must beretrieved from bulk storage during execution. Input or I/O devices canbe coupled to the system either directly or through intervening I/Ocontrollers. The data processing system may include an apparatus may bespecially constructed for the required purposes, or it may comprise ageneral-purpose computer selectively activated or reconfigured by acomputer program stored in the computer.

The foregoing description has been presented for the purposes ofillustration and description. It is not intended to be exhaustive or tolimit the specification to the precise form disclosed. Manymodifications and variations are possible in light of the aboveteaching. It is intended that the scope of the disclosure be limited notby this detailed description, but rather by the claims of thisapplication. As will be understood by those familiar with the art, thespecification may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. Likewise, theparticular naming and division of the modules, routines, features,attributes, methodologies and other aspects may not be mandatory orsignificant, and the mechanisms that implement the specification or itsfeatures may have different names, divisions, and/or formats.

Furthermore, the modules, routines, features, attributes, methodologiesand other aspects of the disclosure can be implemented as software,hardware, firmware, or any combination of the foregoing. The technologycan also take the form of a computer program product accessible from acomputer-usable or computer-readable medium providing program code foruse by or in connection with a computer or any instruction executionsystem. Wherever a component, an example of which is a module or engine,of the specification is implemented as software, the component can beimplemented as a standalone program, as part of a larger program, as aplurality of separate programs, as a statically or dynamically linkedlibrary, as a kernel loadable module, as firmware, as resident software,as microcode, as a device driver, and/or in every and any other wayknown now or in the future. Additionally, the disclosure is in no waylimited to implementation in any specific programming language, or forany specific operating system or environment. Accordingly, thedisclosure is intended to be illustrative, but not limiting, of thescope of the subject matter set forth in the following claims.

What is claimed is:
 1. A method comprising: generating, by one or morecomputing devices, a picking schedule including pick-to-cart routingbased on order data, the picking schedule indicating when to deliver oneor more first items to a pick-cell station, the order data including oneor more first identification codes representing the one or more firstitems located in a pick-to-cart area of a distribution facility, thepicking schedule identifying one or more shipping cartons assigned to betransported by a cart automated guided vehicle (AGV) and into which theone or more first items of the order data may be placed; dispatching, bythe one or more computing devices, the cart AGV according to the pickingschedule, the cart AGV including a drive unit adapted to provide motiveforce to the cart AGV and a guidance system adapted to locate the cartAGV in the distribution facility, the cart AGV adapted to autonomouslytransport the one or more shipping cartons, the one or more shippingcartons adapted to hold items during transportation by the cart AGV andshipment to a shipping address; autonomously navigating, by the one ormore computing devices, the cart AGV through the pick-to-cart areaaccording to the pick-to-cart routing to allow picking of the one ormore first items located in the pick-to-cart area; and autonomouslynavigating, by the one or more computing devices, the cart AGV to thepick-cell station according to the pick-to-cart routing.
 2. The methodof claim 1, wherein the order data includes one or more secondidentification codes representing one or more second items located in ahigh-density storage area of the distribution facility, the pickingschedule includes a modular storage fetching (MSF) routing, and themethod further includes dispatching, by the one or more computingdevices, an MSF AGV according to the picking schedule, the MSF AGVincluding a drive unit adapted to provide motive force to the MSF AGV, aguidance system adapted to locate the MSF AGV in the distributionfacility, and a modular storage unit holder adapted to hold one or moremodular storage units, the MSF AGV adapted to autonomously retrieve theone or more modular storage units from the high-density storage area andtransport the one or more modular storage units to the pick-cellstation, autonomously navigating, by the one or more computing devices,the MSF AGV to a location of the one or more modular storage units inthe high-density storage area, the one or more modular storage unitscontaining the one or more second items, and autonomously retrieving, bythe MSF AGV, the one or more modular storage units from the high-densitystorage area.
 3. The method of claim 2, further comprising autonomouslynavigating, by the one or more computing devices, the MSF AGV from thelocation of the one or more modular storage units in the high-densitystorage area to the pick-cell station according to the MSF routing. 4.The method of claim 2, wherein autonomously navigating the MSF AGV tothe location of the one or more modular storage units in thehigh-density storage area includes autonomously navigating the MSF AGVto a first location of a first modular storage unit in the high-densitystorage area, the first modular storage unit containing a firstparticular item of the one or more second items, and autonomouslynavigating the MSF AGV from the first location of the first modularstorage unit to a second location of a second modular storage unit, thesecond modular storage unit containing a second particular item of theone or more second items, and autonomously retrieving, by the MSF AGV,the one or more modular storage units includes autonomously retrieving,by the MSF AGV, the first modular storage unit from the first locationof the first modular storage unit in the high-density storage area, andautonomously retrieving, by the MSF AGV, the second modular storage unitfrom the second location of the second modular storage unit.
 5. Themethod of claim 4, wherein the second location of the second modularstorage unit is a second pick-cell station.
 6. The method of claim 4,wherein the second location of the second modular storage unit is adifferent location of the high-density storage area than the firstlocation of the first modular storage unit.
 7. The method of claim 2,further comprising autonomously navigating the MSF AGV from the locationof the one or more modular storage units in the high-density storagearea to the pick-cell station; and autonomously delivering, by the MSFAGV, a first modular storage unit to the pick-cell station.
 8. Themethod of claim 2, wherein the MSF AGV is further adapted to stage theone or more modular storage units at a staging area of the pick-cellstation.
 9. The method of claim 2, wherein the MSF AGV is adapted toretrieve multiple sizes of modular storage units.
 10. The method ofclaim 2, wherein the one or more modular storage units include a holdingstructure adapted to hold items, the holding structure adapted tointerface with a retrieval mechanism of the MSF AGV, and the MSF AGVincludes the retrieval mechanism adapted to interface with the holdingstructure to retrieve a given modular storage unit from a modularstorage unit support structure and place the given modular storage unitin the modular storage unit holder.
 11. The method of claim 10, whereinthe retrieval mechanism of the MSF AGV includes a fork coupled with theMSF AGV and configured to lift the given modular storage unit and removethe given modular storage unit from the modular storage unit supportstructure, and the modular storage unit support structure includes ashelf.
 12. The method of claim 10, wherein the modular storage unitholder of the MSF AGV is adapted to hold a plurality of modular storageunits.
 13. The method of claim 12, wherein the modular storage unitholder of the MSF AGV includes a plurality of bays, each bay adapted tohold a modular storage unit, and the retrieval mechanism is adapted toplace the given modular storage unit in any of the plurality of bays.14. The method of claim 2, wherein the pick-cell station includes anoutput device configured to provide picking instructions to a picker,the picking instructions indicating to the picker which of the one ormore second items from the one or more modular storage units to place ina given shipping carton held on the cart AGV.
 15. A method comprising:dispatching, by one or more computing devices, a cart automated guidedvehicle (AGV) according to a picking schedule that includes when todeliver one or more first items to a pick-cell station, the cart AGVincluding a drive unit adapted to provide motive force to the cart AGVand a guidance system adapted to locate the cart AGV in a distributionfacility, the cart AGV adapted to autonomously transport one or moreshipping cartons, the one or more shipping cartons adapted to hold oneor more items during transportation by the cart AGV and shipment to ashipping address, the picking schedule identifying the one or moreshipping cartons assigned to be transported by the cart AGV and intowhich the one or more first items may be placed; dispatching, by the oneor more computing devices, a modular storage fetching (MSF) AGVaccording to the picking schedule, the MSF AGV including a drive unitadapted to provide motive force to the MSF AGV and a guidance systemadapted to locate the MSF AGV in the distribution facility, the MSF AGVadapted to hold a plurality of modular storage units and retrieve theplurality of modular storage units from a high-density storage area andtransport the plurality of modular storage units to a pick-cell station;autonomously navigating, by the one or more computing devices, the cartAGV through a pick-to-cart area according to the picking schedule toretrieve a first item located in the pick-to-cart area; autonomouslynavigating, by the one or more computing devices, the cart AGV to thepick-cell station according to the picking schedule; autonomouslynavigating the MSF AGV to a first location of a first modular storageunit in the high-density storage area, the first modular storage unitcontaining a second item; autonomously retrieving, by the MSF AGV, thefirst modular storage unit from the first location; autonomouslynavigating the MSF AGV from the first location to a second location of asecond modular storage unit, the second modular storage unit containinga third item; autonomously retrieving, by the MSF AGV, the secondmodular storage unit from the second location; and autonomouslydelivering, by the MSF AGV, the first modular storage unit and thesecond modular storage unit to the pick-cell station.
 16. A systemcomprising: a first processor adapted to generate a picking schedule,the picking schedule indicating when to deliver one or more first itemsto a pick-cell station and including a pick-to-cart routing based onorder data, the order data including one or more first identificationcodes representing the one or more first items located in a pick-to-cartarea of a distribution facility, and to transmit a signal including thepicking schedule to a second processor dispatching system, the pickingschedule identifying one or more shipping cartons assigned to betransported by a cart automated guided vehicle (AGV) and into which theone or more first items of the order data may be placed; the secondprocessor adapted to dispatch the cart AGV according to the pickingschedule, the cart AGV including a drive unit adapted to provide motiveforce to the cart AGV and a guidance system adapted to locate the cartAGV in the distribution facility, the cart AGV adapted to autonomouslytransport the one or more shipping cartons, the one or more shippingcartons adapted to hold one or more items during transportation by thecart AGV and shipment to a shipping address; and the cart AGV adapted toautonomously navigate through the pick-to-cart area according to thepick-to-cart routing to retrieve the one or more first items located inthe pick-to-cart area, and autonomously navigate to a pick-cell stationaccording to the pick-to-cart routing.
 17. The system of claim 16further comprising a modular storage fetching (MSF) AGV including adrive unit adapted to provide motive force to the MSF AGV, a guidancesystem adapted to locate the MSF AGV in the distribution facility, and amodular storage unit holder adapted to hold one or more modular storageunits, the MSF AGV adapted to autonomously retrieve the one or moremodular storage units from a high-density storage area and transport theone or more modular storage units to the pick-cell station.
 18. Thesystem of claim 17 wherein the MSF AGV is further configured toautonomously navigate to a location of the one or more modular storageunits in the high-density storage area, the one or more modular storageunits containing a second item, and autonomously retrieve the one ormore modular storage units from the high-density storage area.
 19. Thesystem of claim 18 wherein the MSF AGV is further configured toautonomously navigate from the location of the one or more modularstorage units in the high-density storage area to the pick-cell station,and autonomously deliver the one or more modular storage units to thepick-cell station.
 20. The system of claim 17 wherein the secondprocessor is further configured to dispatch the MSF AGV according to thepicking schedule.